Confusion with links

I’m a bit confused with a scripaction I’m working on that gets called on an
AddLink. It seems that (in this case), whether I am creating the link from
parent to child, or child to parent, the Transaction info is always the
same. If I link the child to the parent, from the child ticket’s web page,
I get the same Transaction data, as if I create the link from parent to
child on the parents web page. The scrip is trying to sync the child
tickets status and owner to the parents, and works fine if I perform the
link from child to parent ($self->TicketObj->DependsOn gives me the right
data), but if I create the link from parent to child, obviously this doesn’t
work. How can I determine who is the parent and child in a ticket-agnostic
way? In other words, I’d like the same behavior if I’m linking from parent
to child, or child to parent. Anyone have any ideas? My immediate thought
is to parse the TransactionObj->Data, but that seems REALLY kludgy to me.
Any thoughts?